Morphological and morphometrical identification of Meloidogyne populations from various crop production areas in South Africa with emphasis on M. enterolobii
Author
Rashidifard, Milad
Author
Fourie, Hendrika
Author
Daneel, Mieke Stefanie
Author
Marais, Mariette
text
Zootaxa
2019
2019-08-22
4658
2
251
274
journal article
25937
10.11646/zootaxa.4658.2.3
6c4ff371-ec38-493c-83b1-6edddccf9f52
1175-5326
3375820
9AA35B64-5307-4438-9C5C-BD01ACA4FFFB
Meloidogyne incognita
(
Kofoid & White, 1919
)
Chitwood, 1949
Figures 3
to 5, 8
Measurements:
Tables 3
,
4
and
8
to 9
Female (n= 88 perineal-patterns; n=5 intact females).
Body pear-shaped and round in posterior part with annulated cuticle. Head aligned well with the rest of body. Stylet narrow, straight,
20–21 µm
long. Stylet knobs transversely ovoid. Dorsal gland opening
3–5 µm
posterior to stylet knobs. Median bulb
67–80 µm
from anterior end, with oval valve (
Fig. 4
). Oesophagus lumen lining expanded, then narrows towards median bulb lining. Neck
140–190 µm
long. Perineal-pattern circular to oval shape, dorsal arch medium high to high, apex of dorsal arch broadly rounded to square, junction between lateral lines usually y-shaped. Phasmids indistinct,
1–2 µm
in diameter, interphasmidial distance
19–30 µm
. Rectal punctuations sparse, usually large, lateral lines indistinct or indicated by forked striae, tail terminus distinct (
Fig. 3
). Vulval slit
20–31 µm
long, anus
10–27 µm
posterior to vulva (
Table 4
).
Male (n= 25).
Body vermiform,
1199–2073
µm
long. Head region aligned to the body and not set off with high and round cap. Stylet
22–26 µm
long, straight, knobs large, ovoid and sloping backward. Dorsal gland opening
3–6 µm
posterior to stylet knobs. Lateral fields areolated from median bulb to tail. Median bulb narrow to elongated followed by narrow isthmus. Excretory pore
115–184 µm
from anterior end. Tail
11–15 µm
long, not annulated. Spicule arcuate,
24–34 µm
long. Gubernaculum short,
6–9 µm
long. Phasmids pore-like, opposite to cloaca.
Second-stage juvenile (n= 59).
Body
331–427 µm
long, straight to curve ventrally, narrow, tapered anteriorly and posteriorly. Head hemispherical, not set off. Stylet
11–16 µm
long, cone straight. Stylet knobs large and sloping backward. Dorsal gland opening
2–5 µm
posterior to stylet knobs. Median bulb enlarged with oval valve. Excre- tory pore
63–91 µm
from anterior end. Tail long
35–61 µm
, conical with tapered end. The hyaline tail terminus defined.
FIGURE 8.
Light microscopic photos of second stage juveniles (J2) of
M. incognita
obtained from roots of agri- and horticul- tural crops in South African production areas during 2015 and 2016. A, B: anterior part of body; C, D: variation of tail shape.
Remarks.
The
M. incognita
population from this study compared well with other populations from
South Africa
(
Kleynhans 1991
). Female specimens from this study, however, differed in: stylet length (
20–21 µm
vs
15–17 µm
) and vulval slit length (
20–33 µm
vs
21–27 µm
) from the population described by
Kleynhans (1991)
. The current male specimens differed from that reported by
Kleynhans (1991)
in: shorter DGO (
2–4 µm
vs
3–7 µm
). The J
2 specimens
differed in: body length (
331–427 µm
vs
362–463 µm
) and tail length (
35–61 µm
vs
49–58 µm
).